Service-meter system for telephone-exchanges.



J" um Mot r 0 R k k S L r hfi w\ Patented July 20,1915.

H. s. TURNER." SERVICE METER SYSTEM FOR TELEPHONE EXCHANGES.

v APPLICATION FILEQ DEC. I9, 1914.

" tlhilti fhifi HUBER? S. TURNER, E SLN DIEGO, CALIFORNIA.

' SERVICE-METER SYSTEM FOR TELEPHONE-EXCHANGES.

menses.

Original application filed .Tune 20, 1914, Serial Ho.8 46,228. Diy-idedand: this application 1914. Serial No. 818,143.

i calls initiated at a substation and obtaining a response at a calledsub-station are automatically recorded by a ser-vlce meter individual tothe line of the calling sub-station.

' The system constituting the subject of this application, is shown anddescribed in an application for Letters Patent of the United States fortelephone systems filed by me June 20, 1914, Serial No. 846,228, ofwhich application the present one constitutes a division. v

While the system is especially adapted for use with telephone systems ofthe common battery type having three conductor multiple jacks at thecentral oiiice, it can readily be adapted to other systems.

In systems of this class it has been the practice to place a servicemeter for recording the calls from a sub-station line in series or inmultiple relation with the winding of the cut-oli relay, used toextinguish the call initiating line signal, and to'actuate the servicemeter by impressing a voltage upon the circuit greater than that usedfor the actuation of the cut-oil relay. This marginal action of theservice meter has been found objectionable in many ways.

One or the objects of my present invention is to overcome these defectsand I accomplish this in the specific way here shown by impressing uponthe circuit comprising the cutpfl relay and service meter in multiplerelation therewith a voltage preferably less than that necessary toactuate the cutoff relay. At the same time providing means whereby thecurrent which actuates the cutoil relay cannot find a path through theoperating winding of the service meter. Another de'l cct in servicemeter systems, wherein the meters are operated automatically when thecalled sub-station responds to its calling signal, is that if thecalling subscriber has hung up his receiver previous to the response oi.the called subscriber and the latter should respond previous to thetaking filed December 19,

operator, the call will still be registered on the calling snbscribersservice meter, notwithstanding the fact that the call has not beencompleted. In my system this defect is overcome.

Another object of the invention is the pro-- vision of means whereby aservice meter for: recordingthe total number of calls attended to by aswitchboard operator is made a part of the equipment individual to eachoperators position, it being impossible to make said service meterrecord unless a connection is made to a sub-station line actuallyinitiat-' ing a call, impossible to make it record but one for each suchconnection made and impossible to make it-record if aconnection is Theob ect in so arvention, reference will now be had to the accompanyingdrawing forming a part of this specification and illustrating onespecific embodiment of my said invent-ion diagrammaticallyl I have shownat A B, two telephone substations, each including a telephone receiver aa transmitter a ,a switch-hook a3, a call bell a", a condenser a andprimary a and secondary a of an induction coil. The elements a and abeing included in. a bridge of the telephone line, which bridge is openwhen the telephone receiver is upon the switch-hook a and which bridgeis closed by the switclrhook a when relieved of the weight of thetelephone receiver. The elements a and a, are included in another bridgepermanently continuous with respect to alternatingcurrents, butnon-continuous with'respect to direct currents. The type of sub-stationoutfit shown is one that I have selected for the purpose of illustratingthe invention, but it is to be understood that I do not limit myself tothe form of sub-station. apparatusshown, for it will be seen as thedescription of the invention is' proceeded with, that the operation ofthe system does not depend upon. the peculiar sub-station of theinvention shown by means of metallic circuits, whose limbs D and G D areconnected with the line springs 'or talking contacts of spring jacks E,E and 13, F A. plurality of spring jacks shown in mul tipie relationwith each line, the lowermost spring jack F and F -constituting theansweri'ng, jacks, while the remaining jacks and E constitute multiplejacks. The limbs C and D also terminate in contacts onthe right and lefthand armature switches of cut-ofi relay G, the limbs of each telephoneline being normally connected by means of-said armature switches and thecontacts normally engaged thereby with a line relay H, the limb G beingconnected with the left hand winding and the limb D being connected withthe right hand winding of said relay, the. other terminals of \K thewindings of said relay being connected through grounded battery Linerelay H is actuated by the removal of the telephone receiver atsub-station A from itssupporting switch-hook by means of a cir cuitwhich may be traced from" transmitter through line (3, left handarmature switch and normal contact of cut-off relay G, left hand windingof line relay H to the live pole of grounded battery'K, through saidbatteryto ground,- through the right hand .windingof line relay H,righthand normal contact and armature switch of cut-ofi relay G, line1'), primary a, switch-hook a completing the circuit through transmitterr. This actuation of line relay H causes its armature switch to close acircuit through line lamp orsignal h which may be traced from groundthrough said armature switchand engaged contact, said line lamp orsignai, grounded battery K to ground, thus completing the circuit,llavihg observed the line signal of the calling sub-station the peratorinserts plug N into the answering jack, F, corresponding to therallihgsubstation, and grasps calling plug N 1 with finger contact device mThis finger contact device consists of an open ring of some suit- 13%able sprinfi metal lined with an insulating substance to prevent contactof the metal portion thereof with the fingeron which it is worn, iscircuit can be traced from the live pole of grounded battery K throughsaid device'm", metallic thimble n of calling plug N in juxtapositionwith it, normal contact of the middle armature switch of the three topones cfcalling relay, winding of operating relay P, sleeve 'co tact ofan swering plug N, thimble of answering jack F, left hand winding ofsub-station service of cut-off ,relay G to ground, thus completing thecircuit through grounded battery K. The armature of the operatingclectrdmagnet'of sub-station servarenas? that can flow through its lefthand winding,

but said armature is maintained attracted thereby when current flowingthrough the right hand winding of said electro-magnet has caused theattraction of said armature. Therefore, the left hand windingconstitutes a locking winding and the right hand winding an operatingwinding for said electromagnet'. v

Both sub-station service meter V and,operators service meter W consistof an electro-magnet and an armature therefor, a train of countingwheels actuated or controlled by. an escapement or other suitable devicemoved by the armature, and a spring switch adapted to open its contactafter said meter has performed its recording function. The mechanicalparts of this service meter are, however, well known in the art and needvention they have been omitted from the drawing. it should also be notedthat for the purpose of clearness in the drawing 1 have omitted variouscircuits and apparatus connected with the operators telephone set andother circuits. and apparatus not di rectly associated with my presentinvention. Y The actuation of operating relay P, due to the circuittraced through its winding, allows current from the live poleof grounded battery'K to flow through the winding of waiting relay R, thelowermost of the three top armature switches of operating relay P andthe engaged contact thereof, normal contact and spring switch r ofwaiting relay 1%, normal contact and spring switch 8 of, answering relayS, winding of answering supervisory relayT, tip of answering plug N, tipspring of answering jack F, limb D, primary a switch-hook a, transmittera limb C, ringspring of answering jack F, ring contact a of answeringplug N, spring switch 8 and its normal con tact of answering relay S,the engaged contacts of the uppermost of. the three top armatureswitches of actuated operating relay 1 theright hand winding of splitrepeating coil U to ground, thus completing the circuit through groundedbattery K.

The-actuation of supervisory relayT, due

to the current flowing through the circuit left hand winding of sub-.

I vides, a portion'pa'ssing through said windthrough the lowermost ofthe two top armature switches of answering relay 8- and its normalcontact, the middle. one of the three top armature switchesof actuatedoperating relay l? and its engaged contact, the winding of operatorsservice meter VV,'s'pring switch of and its contact of the same meter togrounded battery K, completing the circuit through the same. Theoperation of answering relay S is prevented as long as the winding ofthe electro-magnet of operators service meter W remains bridged acrossits winding as described, but the operation of said meteris allowed bythe ourrent that flows through said winding. Therefore, saidelectrormagnet attracts its armature, first operating the recordingmechanism and then breaking the circuit through said winding bydisengaging spring switch 'w from its contact. The bridged circuitacross the winding of answering relay S being thus removed, the latterat once actuates, thereby breaking the connection to the winding ofoperators service meter when the lowermost of the two top armatureswitches of said relay disengages its normal contact. Therefor whenspring switch to of oierators service meter W reen a es its contact, dueto the cutting off of current from said winding when said spring switchdisengaged its contact, current cannotpass' through its winding again toenergize said electro-niagnet. Therefore, its mechanism cannot recordmore than once for every call the operator answers and cannot be made torecord when there is no sub-station initiating a call on the line withwhich an'answering plug may be connected, as in that case there would beno path for the current necessary to actuate supervisory relay T.

The actuation of answering relay S causes he uppermost of its two toparmature switches to engage spring switch 3 before disengaging thelatter from its normal contact, in this way current from the left handwinding of split repeating coil U replaces the current from therighthand winding of the same, without breaking the connection to ground. Atthe same time the lowermost of its two bottom armature switches engagesspring switch 5' before the latter disengages its normal contact, inthis way current from the left hand winding of split repeating coil Ureplaces the current from the winding of waiting relay R, withoutbreaking the connection to the live pole of grounded battery K.

So far as has been described, the circuit through substation. A is nowconnected through supervisory relay T and the left hand windin of splitrepeating coil U and U to the two poles of grounded battery K.

. Operators telephone receiver/m is bridged with sub-station B, forinstance, the operator, still grasping the thimble n of calling plug Nin sucha way that finger contact device m is in electrical contact withit,: tests. the line called for by touching the thimble of one of itsmultiple jacks with the tip of the plug, in a manner well known in theart. If the line tests, not busy, the calling plug N is inserted in themultiple be traced from the grounded terminal of cut-off relay G thewinding of said relay, thimble of multiple jack E sleeve 72. of callingplug N springswitcho and its normal contact of calling relay 0, windingof ringing relay Y, uppermost of the two bottom armature switches andits engaged alternate contact of actuated answering relay S, springswitchr and its normal contact of waiting relay R, contact and lowermostof I ed battery K through the lowermost of the two top armature switchesof said ringing relay Y and its engaged contact, the engaged contact andlowermost of-the three top armature switches of actuated operating relayP to the upper terminal of the winding of waiting relay R. When waitingrelay R releases its armature switches, due, to this short-circuit, thecurrent flowing through the winding of ringing relay Y and spring switchr of waiting relay R passes to the live pole of grounded battery Kthrough saidlowermost armature switch of the two top ones of ringingrelay Y and its engaged contact. The actuation ofcut-off relay G removesline. relay H in the same manner as describedin relation to the removalof line relay H. Therefore, the displayof line lamp or signal 11, isprevented when the ack and a circuit is established which may partyatsub-station B removes the telephone receiver from its switch-hook. Theexchange line apparatus associated with the line. ofsub-station B isshown without a service meter, such as shown at V, as-lines may beconnected together which may or may not have such service metersassociated with their line apparatus. The actuation of ringing relay Yalso closes a circuit which may be traced from ground through ringinggenerator 1, continuous ringing commutator K engaged contact andlowermost of the three bottom armature switches of actuated operatingrelay P, normal contact and bottom armature switch of the shortcircuitedwaiting relay'R, alternate contact and uppermost one of the two bottom.armature switches of actuated ringing relay Y,

- non-inductive resistance tip of plug N tip spring of multiple jack Elimb of I the line of sub-station B, call bell or annunciator a,condenser a limb D ring spring of multiple ack'E ,r1ng contact n ofcalling plug N uppermost contact and armatureswitch of the two top onesof actuated ringing relay Y, right'hand winding of split denser a beforethe removal of said. re

ceiver, allowed the passage of alternating currents only through saidlimbs, but now the passage of direct currents are allowed as well and onthis account a new circuit is now closed which may be traced from the.

live pole of grounded battery K through commuta-tor'M and its brush,lowermost one of the two bottom armature-switches of actuated ringingrelay Y, switch spring z winding of supervisory relay T tip of callingplug N tip spring of multiple jack E limb (1, primary a, switch-hook atransihitter a limb D ring spring of multiple jack E ring contact a ofcalling plug N contact and uppermost armature switch of the. two topones of actuated ringing relay Y, right hand winding of split repeatingcoil U, completing the circuit through grounded battery K.Supervisoryrelay T is actuated by the current flowing through thedescribed circuit and its armature switch closes a circuit which may betraced from the'live pole of grounded battery K, calling supervisorylamp or signal 25*, winding of calling relay O, armature switch andalternate contact of calling supervisory relay T sleeve 91, of callingplug N thimble of multiple-jack E winding of cut-cit relay G to ground,completing the circuit through grounded battery K. The current flowingthrough this circuit causes the actuation of calling relay 0 and bottomarmature manner switch engages spring switch 0 which in turn causesspring switch 0 to break its contact opening the circuit through thewinding of ringing relay Y and thereby causing the latter to release itsvarious armature switches, the engagement of the uppermost one of thetwo bottom armature switches with its normal contact and the engagementof spring switch 12 with its normal contact bridging non-inductiveresistance f across the winding of calling supervisory relay T5 Thelowermost armature switch of the two bottom ones of ringing relay Y. hasat the same time disconnected the live pole of grounded battery K,through commutator M and its brush, from the winding of callingsupervisory relay T but before it did so, current from said pole throughthe right hand winding of split repeating coil U wassubstituted for it;said current flowing through contact and bottom armature switch-ofcalling .relay 0 to normal contact of spring switch y where it makescontact with the latter before the same is separated from its armatureswitch. Simultaneously with the engagement of its contact by the bottomarmature switch of calling relay 0, the uppermost of the three toparmature switches of the latter engages its contact, thus substitutinganother connection to the ring contact a of calling plug N from theright hand winding of split. repeating coil U, before the same is brokenby the corres%)nd ing armature switch of in this way, the currentringing relay flowing through the winding of calling supervisory relay Tis uninterrupted notwithstanding its current connections have beenchanged and as the tip and ring strands of the link connector connectedto calling plug N are now connected to the right hand windings of splitrepeating coil-U and U conversation between sub-stations A and B is nowpossible.

The engagement of the lowermost one of the three top armature switchesof calling relay O-with its contact, closes acircuit which may be tracedfrom said contact through battery X, which is preferably of a very lowvoltage, inner right hand armature switch and contact of actuatedcut-ofi relay G,right hand winding of subf'station service meter V,spring switch o or said and engaged armature switch of answeringsupervisory relay T, lowermost one of the two top armature switches ofactuated answering relay S and its engaged alternate contact, lowermostone of the three top arma- -meter andv its contact, thimble; ofanswering Jack F, sleeve of answering plug N; contact ture switches ofactuated calling relay 0,

completing the circuit with the engaged contact of the same. l The.right hand wlndmg of sub-station service meter V is such that on beingso energized, it pulls up its armaarass? ture, thereby, first operatingits recording mechanism and then breaking the circuit through saidwinding by disengaging. spring I switch from its contact. In thismanner,

battery X is removed from the circuit, as the current flowing throughthe left hand winding of service meter V (as hereinbefore explained) issui'iicient to maintain the attraction of said armature though notsufficient to attract the same, therefore, its armature does not fallback and spring switch '0 remains disengaged from its contact as long ascut-oil" relay Gr remains actuated. In this way I provide means foractuating service meters without increasing the voltage of the currentimpressed on the circuit including the cut-off relay, notwithstandingsaid service meter is in multiple relation to said relay. The onlyobject in breaking the circuit from battery X at the innermost righthand armature switch of cut-off relay G, is

to prevent current from batteryK which passes through the thimbles ofanswering jack F to ground through the left hand winding of servicemeter V and winding of cut-on relay G, from being shunted through theright hand winding of said meter, the right hand windings ofcorresponding service meters associated with idle sub-station lines andthence to ground through the windings of the "cut-off relays associatedwith those lines. By breaking the circuit through said right handwinding at said cut-off relay armature switch, there is no such shuntcircuit. available, as the only path for such a shunt would be throughthe described wind-- ings associated with busy'lines, as eXemplified byengaged contacts with armature switches of said cut-ofl relays, in whichcase. no current would flow through the right hand winding of servicemeter V, as said winding would form part ofpa bridge between circuitshaving the same resistance.

The principle involved being the same as that used-in a W'heatstonebridge, said right hand windings being connected in a way correspondingto the galvanometer usually used with said VVheatstone bridge. 1

.Prev-ious'to the actuation of calling relay 0 and the consequentclosure of the circuit through the right hand winding of service meterV, a circuit through the latter might have been traced from groundthrough the winding of cut-0E relay Gr, left hand wind ing ofservice'meter V, contact and armature switch o of'the same and its righthand winding, innermost right hand armature switch and contact ofactuated cut-off relay G, battery X, contact and lowermost one of thethree-top armature switches of actuated calling relay 0 associated witha link connector other than the'one associated with the describedservice meter and cut-oft relay circult, lowermost of the two toparmature switches and alternate contact of actuatedanswering relay S ofsaid link connector,

sleeve contact of plug N of said link cong nector, thimble contact ofanswering jack F,

left hand winding of service meter V and series with the right handwinding of any service meter V previous to the actuation of said meter,is that of these two circuits in multiple relation. In order to preventthe actuation of said service meter V by the current from battery Xallowed to pass through its right hand winding by this means, saidwinding is of a very low resistance and the left hand winding of thesame meter together with the winding of cut-oil? relay G, is, incomparison, of a high resistance. The winding of answering relay Stogether with supervisory lamp or signal 6 is, in comparison, also of ahigh resistance, and battery X being of a voltage lower than that ofbattery K, suihcient operating current for the right hand winding ofservice meter V is not allowed to pass by means of the circuits traced.In other words, service meter V is only operable when calling relay 0,of the particular link connectorassociated' with the line of thesub-station pertaining to said meter, closes the circuit already tracedthrough battery X and'the right hand winding of said meter and whichcircuit does not include any additional resistance. from groundedbattery K is also kept from right hand winding of service meter V, aswhen such a path is available by the actuation of calling relay O of oneengaged link connector andthe non-actuation of said relay ofanotherengaged link connector, battery X. in series with said winding isbridged across circuits having the same resistance. Therefore, the wellknown Wheatstone bridge circuit is again involved and no cur rent flowsthrough said winding. do not claim as new, the use of the Wheatstonebridge principle, Ti do claim as new its application in the operation ofaservice meter, as described. v

Battery X and the lines connecting the same to the innermost right handcontact'of cut ofii-relay G and contact of, the lowermost one of thethree top armatureswitches of calling relay 0, be common to the enexchange or ccnnnon only to groups of said cutoff: reiays and, groups oflink connectors, sucn as that' shewn in the drawings,

Current i flowing through battery X in series with the While Isubstation B replace the receiver on its tacts of calling plug N Whenthe connected sub-stations A and B have completed their conversationsand have replaced their respective telephone receivers upon theirswitch-hooks, the armature of the controlling electro-magnet of servicemeter V is released and said meter is placed in position to recordagain. Should the party at switch-hook first; thensthe circuit fordirect current is at once broken through primary a and switch-hook asupervisory relay T releases its armature switch, breaking the circuitthrough the winding of calling relay 0, the armature switches of thesame thereupon resuming their normal condition, opening all the circuitsthrough the tip, ring and sleeve con- Due to the opening of the circuitthrough sleeve contact n of calling plug N cut-oil relay G isdeenergized, thereby releasing its armature switches which upon engagingtheir con tacts connect line relay H to the limbs C and D of the line ofsub-station B, so that line signal 7& will again respond on the removalof telephone receiver a from itsswitch-hook;

When the party at sub-station A replaces the receiver upon itsswitchhook, the circuit for direct current is broken, as hereinbeforedescribed in relation to substation B, the deenergization of answeringsupervisory relay T breaking the circuit 4 through the winding ofanswering relay S,

the. armature switches of the same there' upon resuming their normalcondition and opening all the circults through the tlp, ring and sleevecontacts of answerlng plug N.

- Due to the opening of the circuit through the control of substation Ain the same the receiver of sub-station A" upon its.

the sleeve contact of said plug, cut-01f relay G is deenergized andconsequently the left hand winding of service meter V, the release ofthe armature of the controlling magnet of the same allowing springswitch v to reengage its contact, thereby placing said meter in anoperable condition- Line relay H and line lamp or signal h is restoredto manner as described in relation to sub-station B.

It will be observed that means are provided whereby it the calling partyreplaces switch-hook previous to the response of the calledsub-stationB, the consequent deenergization of answering relay S wouldcause the de'e'nerg-ization of ringing relay Y by opening the circuitthrough the winding of the same when the uppermost of the two bottomarmature switches of said answering relay S disengages its contact. Saiddeenergization of ringing relay Y and the con sequent release of itsarmature switches not only prevents the'ringing of the called substations call bell, but prevents the actuation of calling relay 0 shouldthe called sub-sta- Therefore, calling ually operated key or button forthe memes? throngh limbs tion respond, as the circuit deenergization Cand D is opened by said of ringing relay Y. Therefore, should thecalling party replace his receiver upon its switch-hook previous .to'theresponse of the called sub-station, thereby abandoning the call hehas-initiated, the service meter associated with said-calling partysline wili not register the call should the called party subsequentlyrespond.

When answering plug H is inserted in. a

- sprindjack and the'thimble of calling plug is grasped by fingercontact device m, a circuit has been traced from ground through cut-ofi"relay G and service meter vided current at the thimbles of thesprin'gjacks is not sufficient to so energize said winding of operating relay lAs the cir cuit through the winding of operators service meter W isclosed by the engagementcf the middle one of the three top armatureswitches of operating relay P, it'will, be

seen that said meter will notrecord if a con- '1 nection is made to abusy line. i instead of energizing operating relay if by means of thedescribed finger contact de y 'vlce, the line leading to thimble n ofcalling plug N could be connected to one contact oi a key or button, thelive pole of grounded battery K being connected tothe other con--tact-of the same, thus substituting a man- ('33 scribed finger contactdevice.

/Vhile I have shown and described my i'" vention with respect to certaindetails'ar combinations it is to be understood that l do not wish tolimit myself thereto,.many

"viations and modiiications being possiblewithout in any way departingfrom the L spirit and scope of invention.

VVhat I claim is 2- 1. lira system of the class described, a Wheatstonebridge circuit, a. service meter individual to each of a'pluralityofsub-station lines'and having a winding connected in the bridge wire ofsaid circuit, and means to energize said winding to cause said meter toreccrd.

2. In. a system of the class described, a VVhea tstone bridge circuit, aservice meter having a winding connected in the bridge wire, across thearms of said circuit and another w nding forming a part of an arm ofsaid circuit, and means to energize said first mentioned winding tooperate said meter. i

3. In a system of the class described, a Wheatstone bridge circuit, aservice meter having a winding balanced across the arms of said circuit,and means to energize-said winding to operate said meter, by unbalancingsaid Wheatstone bridge circuit without altering the resistance of saidarms.

4. In a system of the class. described,- a

"Wheatstone bridge circuit, a source of electricity to energize thesame, a service meter having awinding balanced across the arms of saidcircuit, and means including a separate source of electricity to impresscurrent upon said winding to energize the same.

- 5. A telephone exchange system, -includ'-' ing telephone linesextending from substations to van exchange, connecting apparatus andlink connectors for connecting said substations, a'cut-ofi' relay, aservice meter associated with a sub-station line, an electromagnetforoperating said meter and comprising an operating winding and a lockingwinding in branch relation .to said'operating winding and in series withthe Winding of said cut-.ofi relay, automatic means to render saidmeterinoperative when the line associated therewith 1s a called line, andauwinding and' in series with the winding of said cut-off relay,automatic means to render said meter lnoperatlve when the hue asso- Yciated therewith is a called line, automatic means including saidconnecting apparatus to render thesame operative Whensaid line is acalling line and the called sub-station connected thereto has respondedto its calling signal, and means under thecontrol of apparatus at thecalling sub-station previous to the response of the called sub-station,whereby said meter is rendered inoperative by the subsequent responseofsaid called sub-station. 4

7, A telephone exchange system, includ ing telephone 'linesextendingfrom sub-stations to an exchange, connecting apparatus and linkconnectors forconnecting said substat1ons,,a cut-off relay,aSQIIVCG'IIIBtGI associated with. a sub-station line, an electromagnetfor operating-said meter and com prising an operating winding andalocking Winding in branch relation to said operating winding and inseries with the winding of K said cut-oil relay, and means wherebycurrent to-actuate said cut-0E relay is prevented from flowing throughsaid operating ,Wind- 1n 8. A telephone exchange system, includingtelephone lines extending from sub-stations to an exchange, connectingapparatus and link connectors for connecting said substations, a cut-offrelay, a'service meter associated with a sub-station line, an electromagnet for operating said meter and comprising an operating winding anda locking Winding in branch relation to said operating winding and inseries with the winding of said cut-ofi' relay, means whereby current.to actuate-said cut-0E relay is prevented from flowing'through saidoperating winding, and means under the control of apparatus at a calledsub-station to impress operating current on said operating winding ofsaid meter when the same is associated to I With'the line of a callingsub-station which is connected to saidcalled sub-station.

9. A telephone exchang system, incluct ing telephonelines extendi g fromsubstations to an exchange, connecting apparatus and link connectors forconnecting said sub stations, a cut-off relay, a sepvice meterassociated with a sub-station inc, an electromagnet for operating saidmeter. and comprising an operating winding and a locking winding inbranch relation to said operating winding and in series with the windingof said cut-off relay, means whereby current to. actuate said, cut-offrelay is prevented fromilowing through said operating winding, andmeansunder the control of apparatus at a called sub-station to impressoperating current on said operating Winding of said meter when the sameis associated with the line of a calling sub-station which is connectedto said called sub-station, and means under the control of apparatus, at

said calling sub-station and operative previous to the aforesaid calledsub-station means to prevent the impression of said operating current onsaid operating winding. I

'10. A telephone exchange system, including telephone lines extendingfrom sub-stations to' an exchange having line signaling apparatus forsaid telephonelines, connect-v ing apparatus and link connectors forconnecting said sub-stations, a. service meter associated with asub-station line and having a controlling electro-magnet provided with alocking and an operating winding, a cut-off relay for controlling saidline sig-' naling apparatus governed by said connecting apparatus and inseries with said locking winding, said operating'winding being in branchrelation to said locking Winding,

the actuation of said cut-off relay closing a circuit through saidoperating winding and connecting the same to a limb of-a circuit commonto a plurality of said meters, said operating winding being therebyincluded in a bridge across circuits having the samenecting apparatusand link connectors for connecting said sub-stations; a source ofelectricity, a service. meter. associated. with a sub-station lineandhaving a controlling electro-magnet provided with a locking and anoperating winding, a cut-ofi relay for controlling said line signalingapparatus governed by said connecting apparatus and in series with saidlocking winding, said operating windingbeing in branch relation to saidlocking winding, the actuation of said cut-ofi relay closing a circuitthrough said operating winding and connecting the same to a limb of acircuit common to a plurality of said meters, said operating windingbeing thereby included in a bridge across circuits having the sameresistance,

whereby current from said connecting appa ratus to actuate said cut-ofi.relay is prevented from being shunted through said operating winding,and means under the control of apparatus at a called sub-station toconnect said limbthrough said source of electricity to said windings inbranch relation to each other, thereby causing the operation of saidservice meter by current from said source flowing through said operatingwinding. 7

12. A telephone exchange system, including telephone lines extendingfrom sub-stations to an exchange having line signaling apparatus forsaid telephone lines, connecting apparatus and link connectors forconnecting, said sub-stations, a source of electricity, aservice meterassociated with a' sub-station line and having a controllingelectromagnet provided with a locking and an operating winding, acut-ofl relay for controlling said line signaling apparatus governed bysaid connecting apparatus and in series with said locking winding, saidoperating winding being in branch relation to said locking winding, theactuation of said cut-off relay closing a circuit through said operatingwinding and connecting the same to a limb of a circuit common to a.plurality of said meters, said operating winding being included inbridge across circuits having the same. resistance, whereby current fromsaid connecting apparatus toactuate said cut-off relay is prevented frombeing shunted through said operating wlndmg, and means under 'thecontrolof apparatus at a calledsub-station to connect said limb through saidsource of electricity to said windings in branch relation to each other,thereby causing the operation of said service meter by current from saidsource flowing through said operating winding, and means under thecontrol of apparatus at the calling sub-station and operative previousto the aforesaid called sub-station means to prevent said connection tosaid windings by opening the circuit thereto, thereby preventing the,operation of said service meter. i

13. A telephone exchange system, including telephone lines. extendingfrom sub-stations to an exchange having line signaling apparatus forsaid telephone lines, connectmg apparatus associated with linkconnectors for connecting said sub-stations, connecting means for saidlink connectors associated with said lines, a cut-off relay having itswinding in a local circuit closed through a contact of said connectingmeans when one of said link connectors is engaged therewith, a servicemeter associated with a sub station line, an .electro-magnet foroperating said meter, a winding On said electro-magnet one terminal ofwhich is also'connected to said contact of said connecting means theother terminal being connected to a limb of a circuit common to aplurality or" said service meters by the actuation of said cut-ofi"relay, said winding thereupon forming part of a bridge across circuitshaving the same resistance, whereby current from said connectingapparatus flowing through said link connector engaged with said contactto actuate said cut-off relay is prevented from being shunted throughsaid winding.

14. A telephone exchange system, including telephone lines extendingfrom substations to an exchange having line signaling apparatus for saidtelephone lines, connecting apparatus associated with link connectorsfor connecting said sub-stations, connecting means for sald'lmkconnectors associated with said-lines, a source of electricity and asecond source of electricity of higher voltage than the first mentionedsource, a

cut-off relay for controlling said line signaling apparatus and havingits winding in a local circuitv closed through a contact of saidconnecting means when one of said link connectors is engaged therewith,a service m'e-,

ter associated with a'sub-station line, an electro-magnet foroperatingsaid meter, a winding on said electro-magnet one terminal ofwhich is also connected to said contact of said connecting means theother ter minal-being connected to a limb of a circuit tion to connectsaid limb common to a plurality of said service meters through saidfirst mentioned source of electricity to said contact of said connectingmeans, thereby causing the operation of said service meter by currentfrom said source flowing through said winding.

15. A telephone exchange system, including telephone lines extendingfrom sub-stations to an exchange having line signaling apparatus forsaid telephone lines, connecting apparatus associated with linkconnectors for connecting said sub-stations, connecting means for saidlink connectors associated with said lines, a source of electricity anda second source of electricity of higher voltage than the firstmentioned source, a cut-015i relay for controlling said line signalingapparatus and having its winding in a local circuit closed through acontact of said connecting means when one of said link connectors isengaged therewith, a service meter associated with a sub-station line,an electr c-magnet for operating said meter, a winding on saidelectro-magnet one terminal of which is also connected to said contactof said connecting means the other terminal being'connected to a limb ofa ,cir-, ouit common to a plurality of said service meters by theactuation of said cut-off relay,

said winding thereupon forming part of a bridge across circuits havingthe same resistance, whereby current from said connecting apparatus andsaid second mentioned source of electricity flowing through said linkconnector engaged with said contact to actuate said cut-off relay ispre'vented'from being shunted through said winding, and means under thecontrol of apparatus at a called sub-station to connect said limb commonto a plurality of said service meters through said first mentionedsource of electricity to, said contact of said connecting means, therebycausing the operation of said service meter by current from said sourceunder the control of apparatus at the calling.

flowing through said winding, and means sub-station and operativeprevious to the aforesaid called sub-station means toprevent theconnection to said contact by opening the circuit thereto, therebypreventing the operation of said service meter.

16. A telephone exchange system, including telephone lines extendingfrom sub-stations to an exchange having line signaling apparatus forsaid telephone lines, connecting apparatus associated with linkconnectors for connecting said sub-stations, a service meter associatedwith a sub-station line,

a cut-off relay governed by said connecting apparatus for controllingsaid line signaling apparatus and for closing a circuit through saidservice meter, said cut-off relay having its winding in a local circuitclosed by means of one of said link connectors when connected toa-s'ub-station line, the actuating electro.-magnet of said service meterhaving a locking winding included in the samelocal' circuit and anoperating winding in branch relation to said locking winding but adaptedto be energized by a current of lower voltage than that, required toactuate said cut-off relay, and means whereby after the recording of acall on said service meter, its operating winding is permanently removedfrom said branch relation until the calling electro-magnet of saidservice meter having alocking winding includedin the same local clrcuitand an operating winding in branch relation to said locking winding,means whereby the current in said'local circuit is prevented frompassing through said operating winding to operate the same, said meansincluding a connection from said operating winding to a limb of acircuit common to a plurality of'said service meters, said connectionbeing made only on the actuation of said cut-off relay, whereby saidoperating winding alwaysforms part of a bridge across circuits havingthe same re sistance when so connected, and means whereby after therecording of-a call on said meter, its operating winding is permanentlyremoved from said branch relation until the calling link connectorbecomes idle, said means including a spring switch associated With themechanism of said meter which breaks the, connection through saidoperating winding after the call has been registered, the currentflowing through said locking winding thereupon maintaining saidconnection open.

18. A telephone exchange system, including telephone lines extendingfrom sub-stations to an exchange having line signaling apparatus forsaid telephone lines,-connecting apparatus associated withlinkconnectors for connecting said sub-stations, a service meterassociated with a substation line,

' oi? said link con ectors is connected to a substation line, theactuating electroanagnet of said meter having a locking winding included in the same local circuit and an operating winding in branchrelation to said locking winding but adapted to be energized by acurrent of lower voltage than that required to actuate said cut-oilrelay provided there is no other resistance in circuit, means wherebythe current of higher voltage in said local circuit is prevented frompassing through said operating winding to operate the same, said meansincluding a connection from said operating winding to a limb oi acircuit common to plurality of said meters, saidconnection being madeonly on the actuation of said cut-elf ay, whereby said oi'ieratingwinding always forms part of a bridge across circuits having the sameresistance when so connected, and means whereby after the recording of acall on said meter its operating winding is permanently removed duringan established connection by one oi said link connectors "from. saidoperative connection with said current of lower voltage, said meansincluding a spring switch associated. with the mechanism of said meterwhich breaks the connection through said operating winding after thecall has. been registered, the current flowing through said lockingwinning thereupon maintaining said connection open.

19. A telephone exchange system, includinc; telephone lines extendingfrom sub-stations to an exchange, link connectors terminating inanswering and calling plugs to connect said substations, an answeringrelay and a. calling relay associated with each of said link connectors,a cut-oii relay, a service meter associated with the exchange apparatusof a substation line and actuated by an electro-magn'et only when saidsub-station is a calling one and has been connected by one of said linkconnectors to a' called sub-station that has responded to its callingsignal, an operating winding on said electromagnet, the operatingcircuit of which includes a source of electric energy, an armatureswitch and normally iscngaged contact of said calling relay, an armatureswitch and normally disengaged contact oi said answering relay, sleevecontact of said answerin plug, an armature switch-and normally engagedcontact of said electroanagnet and an arma ture switch and normallydisengaged eontact of said cut-oil relay, said circuit being closed bythe actuation of said calling relay, means under the control of a'irmratus at said calling sub-station to maintain the actuation of saidcut-oft relay and said answering relay, and means under the control ofparatus at said called sub-station to actuate said. calling relayprovided said answering relay is in its actuated condition, the 65651-gization of said operating winding caus the operation of said servicemeter first and then the disengagement of said armature switch of saidelectro-magnet from its contact, thus opening the circuit through saidoperating winding, and a locking windii 1 on said electro-magnet inseries with said cutoil' relay to maintain said disengaoe meat. I

20. A telephone exchange system, including telephone lines extendingfrom tions to an exchange, apparatus at said substations for signalingan operator at exchange, link connectors to connect said sub-stations, aservicemeter common to a group of said linkconnectors for automaticallyrecording the calls answered by operator assigned to said group, anelec' 5 magnet for operating said and i operating circuit therefor,operator co trolled means for closing said circuit ui n-3, one 0-; saidlink connectoi s is connected. a calling line, means to render saidmeter in operative to record a call unless link connector is soconnected, and means render said meter inoperative, after harn recordedonce, by the subsequent mani 5 tion ot said apparatus at a sub-station,on said operating circuit is again closed by operator controlled meanssubsequent to manipulation.

2i. A telephone exchange-system, inclu telephone lines extending fromSllb'uc tions toa-n exchange, apparatus at said i stations for signalingan operator at 5 exchange, link connectors to connect saidslim-stations, a supervisory relay and an answering relay, a servicemeter common to a group of said link connectors for automaticallyrecording the calls answered by an operator assigned to said group, anelec tro-magnet for operating said meter and a: operating circuittherefor, operator controlled means for closing said circuit when one ofsaid linkconnectors is connected to a calling line, means whereby thenon-energi- #ation of said supervisory relayrenders said meterinoperative to record a call unless link connector is so connected, andmeans wherebythe energization of said answering relay renders said meterinoperative to re cord more than once for each call answered by saidoperator.

22. A telephone exchange system, including telephone lines extendingfrom sub stm tions to an exchange, apparatus at said substations forsignaling an operator at saideXchange, link connectors to connect saidsubstations, a service meter common to a group of said link connectorsFor automatically recording the calls answered by an op meme? eratorassigned to said group, means controlled by said operator for operatingsaid meter, means to render said meter inoperative to record a callunless one of said link connectors is first connected to a linewhosesub-station is signaling, said means including an electro-magnetfor operating said meter, a circuit including jack contacts associatedwith said sub-stationlines and contacts on answering plugs associatedwith said link connectors, for the transmission of I current to thewinding of said electro-magnectors terminating in answering and callingplugs to connect said substations, a service meter for automaticallyrecording the calls answered by an operator, and means to render saidmeter inoperative to record a call if one of said link connector isconnected to a busy line.

24. A telephone exchange system, including telephone lines extendingfrom sub-stations to a multiple switchboard, link connectors terminatingin answering and calling plugs to connect said sub stations, a servicemeter for automatically recording the calls answered by an operator, andmeans to render said meter inoperative to record a call if one of saidlink connectors is connected to a busy line, said means includingan'operating circuit for said meter, operator controlled means theactuation of which is essential to the completion of said circuit, saidmeans being operative only by the full force of the current which canpass through a local circuit associated with an idle line, said meansbeing inoperative if said link connector is connected to a busy line.

25. A telephone exchange system, including telephone lines extendingfrom sub-stations to an exchange, link connectors to connect saidsub-stations, a service meter for automatically r cording the callsanswered by an operator, and meansto render said meter inoperative torecord more than once for each call. answered, said means including anelectro-magnet and an operating circuit therefor to operate said meter,an answering relay, and operator controlled means essential t9 establisha connection by one of said link connectors to'bridge the winding ofsaidelectro-magnet across the winding of said answering relay to prevent theactuation of said relay, a spring switch adapted to open the circuitthrough said electro-magnet, after said service meter has operated, topermit the actuation of said relay, and an armature switch associatedwith said relay to prevent the closing of said circuit of saidelectromagnet during the actuation of said relay.

26 A telephone exchange system including telephone lines extending fromsub-sta tions to an exchange, link connectors to connect saidsub-stations, an operators telephone set, a service meter forautomatically recording the calls answered by an operator, and means tocompel the operation of said meter before said operators telephone setis telephonically connected to a line initiating a call, and meanscontrolled by said meter on the completion of its operation in register-I ing a call to automatically connect said operators telephone set tosaid line.

27. A telephone, exchange system, including telephone lines extendingfrom sub-stations to an exchange, link connectors to connect saidsub-stations, an operators telephone set, a service meter forautomatically recording the calls answered by an operator, and means tocompel the operation of said meter before said operators set istelephonically connected to a line initiating a call, and meanscontrolled by said meter on the completion of its operation in recordingacall to automatically connect'said operators telephone set to saidline, said means includ ing an electro-magnet and an operating circuittherefor to operate said meter, an answering relay, and operatorcontrolled meansessential to establish a connection -by one of saidlinkconnectors to bridge the winding of said electro-magnet aroundthewinding of said answering relay to prevent the actuation of saidrelay, a spring switch adapted to open the circuit through saidelectro-mags net, after the service meter has operated, to permittheactuation of said relay, and acircuit closed by the actuation of saidrelay to telephonically connect said operators telephone set to saidline initiating a call.

In testimony whereof I affix my signature in presence of two witnesses.

HUBER-T S. TURNER.

' Witnessesz FRANCIS S. MAGUIRE, J. H. Horn.

